Population structure, phenotypic information and association studies in long-generation crops

Poster presented at Generation Challenge Program Annual Research Meeting. Sao Paulo (Brazil), 12-16 Sep. 200

Obstruction theory on 8-manifolds

This note gives a uniform, self-contained, and fairly direct approach to a variety of obstruction-theoretic problems on 8-manifolds. We give necessary and sufficient cohomological critera for the existence of almost complex and almost quaternionic structures on the tangent bundle and for the reduction of the structure group to U(3) by the homomorphism U(3) --> O(8) given by the Lie algebra representation of PU(3).Comment: 19 page

Rules of Engagement: design attributes for social interactions

We present a taxonomy for the design of workplace “break” spaces. The taxonomy can be used to identify aspects of current spaces that are either successful or problematic. From this analysis, we demonstrate how the taxonomy can be used to identify opportunities for computer mediated augmentation of spaces, and how such designs can be validated against this taxonomy

Probing Intermediate Mass Higgs Interactions at the CERN Large Hadron Collider

We analyze the potentiality of the CERN Large Hadron Collider to probe the Higgs boson couplings to the electroweak gauge bosons. We parametrize the possible deviations of these couplings due to new physics in a model independent way, using the most general dimension--six effective lagrangian where the SU(2)_L x U(1)_Y is realized linearly. For intermediate Higgs masses, the decay channel into two photons is the most important one for Higgs searches at the LHC. We study the effects of these new interactions on the Higgs production mechanism and its subsequent decay into two photons. We show that the LHC will be sensitive to new physics scales beyond the present limits extracted from the LEP and Tevatron physics.Comment: 13 pages, 1 figure included using epsfig, RevTe

Pairwise Force SPH Model for Real-Time Multi-Interaction Applications

In this paper, we present a novel pairwise-force smoothed particle hydrodynamics (PF-SPH) model to allow modeling of various interactions at interfaces in real time. Realistic capture of interactions at interfaces is a challenging problem for SPH-based simulations, especially for scenarios involving multiple interactions at different interfaces. Our PF-SPH model can readily handle multiple kinds of interactions simultaneously in a single simulation; its basis is to use a larger support radius than that used in standard SPH. We adopt a novel anisotropic filtering term to further improve the performance of interaction forces. The proposed model is stable; furthermore, it avoids the particle clustering problem which commonly occurs at the free surface. We show how our model can be used to capture various interactions. We also consider the close connection between droplets and bubbles, and show how to animate bubbles rising in liquid as well as bubbles in air. Our method is versatile, physically plausible and easy-to-implement. Examples are provided to demonstrate the capabilities and effectiveness of our approach

Perkutane transluminale Angioplastie (PTA) von iliakalen und femoropoplitealen Gefäßobstruktionen:Früh- und Langzeitergebnisse bei Patienten eines interdisziplinären Gefäßzentrums

In der vorgelegten Dissertation werden die Ergebnisse von 1582 perkutanen transluminalen Angioplastien von iliakalen, femoropoplitealen und kruralen Gefäßokklusionen im Beobachtungszeitraum 1994 bis 2001 evaluiert. Die Kontrolluntersuchungen auf etwaige Reokklusionen wurden in Form einer digitalen Subtraktionsangiographie post interventionem und mittels Bestimmung der Dopplerindices durchgeführt. So wurden Daten von 7106 dopplersonographischen Nachuntersuchungen aufgelistet und statistisch hinsichtlich einer eventuellen Veränderung des Interventionsergebnisses analysiert. Der durchschnittliche Ankle-Brachial-Pressure-Index (ABPI) stieg im gesamten Studienzeitraum um 0,13 (20,6%) von 0,63 +-0,24 präinterventionell auf 0,76 +-0,27 postinterventionell. Direkt nach PTA betrug der ABPI durchschnittlich 0,84 +-0,18. Die Offenheitsraten nach 7 Jahren betragen 71,4%, die Komplikationsrate liegt bei 6,7%, im Vergleich mit der aktuellen Studienlage sind dies sehr gute Ergebnisse

UVA irradiation of human skin vasodilates arterial vasculature and lowers blood pressure independently of nitric oxide synthase

The incidence of hypertension and cardiovascular disease correlates with latitude and rises in winter. The molecular basis for this remains obscure. As nitric oxide (NO) metabolites are abundant in human skin we hypothesised that exposure to UVA may mobilise NO bioactivity into the circulation to exert beneficial cardiovascular effects independently of vitamin D. In 24 healthy volunteers irradiation of the skin with 2 Standard Erythemal Doses of UVA lowered BP, with concomitant decreases in circulating nitrate and rises in nitrite concentrations. Unexpectedly, acute dietary intervention aimed at modulating systemic nitrate availability had no effect on UV-induced hemodynamic changes, indicating that cardiovascular effects were not mediated via direct utilization of circulating nitrate. UVA irradiation of the forearm caused increased blood flow independently of NO-synthase activity, suggesting involvement of pre-formed cutaneous NO stores. Confocal fluorescence microscopy studies of human skin pre-labelled with the NO-imaging probe DAF2-DA revealed that UVA-induced NO release occurs in a NOS-independent, dose-dependent fashion, with the majority of the light-sensitive NO pool in the upper epidermis. Collectively, our data provide mechanistic insights into an important function of the skin in modulating systemic NO bioavailability which may account for the latitudinal and seasonal variations of BP and cardiovascular disease.Journal of Investigative Dermatology accepted article preview online, 20 January 2014

Atmospheric lepton fluxes at ultrahigh energies

In order to estimate the possibility to observe exotic physics in a neutrino telescope, it is essential to first understand the flux of atmospheric neutrinos, muons and dimuons. We study the production of these leptons by high-energy cosmic rays. We identify three main sources of muons of energy E > 10^6 GeV: the weak decay of charm and bottom mesons and the electromagnetic decay of unflavored mesons. Contrary to the standard assumption, we find that eta mesons, not the prompt decay of charm hadrons, are the dominant source of atmospheric muons at these energies. We show that, as a consequence, the ratio between the neutrino and muon fluxes is significantly reduced. For dimuons, which may be a background for long-lived staus produced near a neutrino telescope, we find that pairs of E ~ 10^7 GeV forming an angle above 10^-6 rad are produced through D (80%) or B (10%) meson decay and through Drell-Yan proceses (10%). The frequency of all these processes has been evaluated using the jet code PYTHIA.Comment: 10 pages, 4 figures; published versio

Allopurinol and oxypurinol are hydroxyl radical scavengers

AbstractAllopurinol is a scavenger of the highly reactive hydroxyl radical (k2 approx. 109 M−1s−1). One product of attack of hydroxyl radical upon allopurinol is oxypurinol, which is a major metabolite of allopurinol. Oxypurinol is a better hydroxyl radical scavenger than is allopurinol (k2 approx. 4 × 109 M−1s−1) and it also reacts with the myeloperoxidase-derived oxidant hypochlorous acid. Hence the protective actions of allopurinol against reperfusion damage after hypoxia need not be entirely due to xanthine oxidase inhibition